1. Field of the Invention
The present invention relates to an optical semiconductor based illuminating apparatus.
2. Discussion of the Background
An optical semiconductor such as a light emitting diode (LED) or a laser diode (LD) is one of the components that have been recently spotlighted widely as an illuminating apparatus due to lower power consumption, a longer lifespan, more excellent durability, and significantly higher brightness as compared with an incandescent lamp and a fluorescent lamp.
Recently, the optical semiconductor has tended to be utilized for downlight illumination.
In the downlight mainly having a form in which an illuminator is buried in a ceiling, the illuminator is hardly exposed, such that a ceiling surface is seen in a state in which it is properly arranged. Meanwhile, in the downlight, it is necessary to select an illuminator having an appropriate function and predict light distribution according to a required space presentation plan.
In the downlight as described above, a distance, an interval, and the like, should be necessarily observed by light distribution data suggested by a manufacturer in order to obtain a normal illumination effect.
However, since a downlight using an optical semiconductor, particularly, a power supply unit of the downlight is positioned at an upper side of a heat sink or a side of an illuminating apparatus, a wiring is complicated and exposed to the outside, such that it is difficult for a worker to perform work or the worker is exposed to an electrical risk.
Further, in the downlight using the optical semiconductor, the power supply may be mounted at the upper side of the heat sink. In this case, a space is insufficient at an upper side of a ceiling surface due to the power supply, such that there may also be a limitation in installing the downlight.